Just a quick teaser. Unfortunately, it appears that Illinois has been annexed by Minnesota. While it's kind of humorous to see people cutting what looks like mountain passes for the sidewalks into the mounds of snow piled on every street corner, it doesn't make for a conducive environment for working on my bike or riding

Looks like they're on sale right now, too, so you can get them for under $100.

The eyes are narrower than the stock shocks, so you'll need some sort of way to fill the space. I went to Farm & Fleet and got a handful of 3/8" washers that fit practically perfectly over the stock bolt. (I know, I'm mixing SAE and Metric, but there's not a whole lot of choice from metrically-challenged American hardware stores...)

I do, but I only had 1/2 hour between when I got home from work and when I had to go to band practice, so that's all I got done. And I don't think the temp has climbed out of the single digits since then, so it's been too cold to work in a garage that's not heated or insulated...

Also, I had to make trip 1 to the hardware store to get the aforementioned washers.

I'm kind of glad I didn't put it all together then, anyway, because as OAD and I looked at the pic, we think I might be able to turn the shock around, so it can still be slid up out of the way when changing tires instead of having to be removed every time. We'll see...

The general view seems to be that the quality of the units are suspect, although some fettling by someone who knows what they're doing can yield good results; and hey...even if they turn out to be rubbish, at least they are sub$100 rubbish, not $300+ rubbish, so they might be worth a shot

Looks like they're on sale right now, too, so you can get them for under $100.

The eyes are narrower than the stock shocks, so you'll need some sort of way to fill the space. I went to Farm & Fleet and got a handful of 3/8" washers that fit practically perfectly over the stock bolt. (I know, I'm mixing SAE and Metric, but there's not a whole lot of choice from metrically-challenged American hardware stores...)

You should be able to locate a Fastenal store in your area that could take care of your metric requirements.

There isn't one in my town, but there are several in the Quad Cities, making them about 1/2 hour away. In this case, I really don't care if they're an exact fit or not, since I'm just using them as shims. Plus they're probably cheaper at Farm & Fleet at $1.50 a pound...

I'll have to keep that in mind the next time I really need Metric, though. Thanks!

Is there a secific advantage to using these? Or are they just a replacement for worn OEM shocks?

There's a couple of advantages. The air pressure in the shock is adjustable, so you can control the rebound rate. The spring adjustors are threaded, so they're continuously adjustable instead of having 4 pre-defined stops.

I've only about about 20 miles on the new shocks, so I really can't give a good review yet. Hopefully soon...

They certainly don't work worse than stock so far, for what that's worth...

I recently read on an old bike forum that these RFY units are a straight knock-off of Ohlins units. It was suggested in one of the posts that a competent suspension shop with Ohlins experienc should be able to rebuild/fettle these cheap Chinese units to almost equal the real things.

I recently read on an old bike forum that these RFY units are a straight knock-off of Ohlins units. It was suggested in one of the posts that a competent suspension shop with Ohlins experienc should be able to rebuild/fettle these cheap Chinese units to almost equal the real things.

ANy experience/comments???

I have no idea about that. Sounds possible, but I don't know anyone/anywhere around here that I'd trust to rebuild shocks for me...

OAD, I know you got a set of these for the Cannonball bike. Have you gotten a chance to put them through their paces yet? What are your impressions of them?

I've done another 300 miles, but still don't have anything to add to what I said before...

are the 13.5" shocks too short for a MP3 400 or the 14.5" ones better.

That's a really good question. When making the lowering brackets, OAD calculated that you didn't want to drop them more than 2". With a shorter stroke length than stock on these shocks, though, it might be OK. I'm really not sure.

If it was me, I'd go with 14" or 14.5" ones to be safe. That's basically what I have now, with my 16" shocks with about a 2" drop with the lowering brackets.

are the 13.5" shocks too short for a MP3 400 or the 14.5" ones better.

That's a really good question. When making the lowering brackets, OAD calculated that you didn't want to drop them more than 2". With a shorter stroke length than stock on these shocks, though, it might be OK. I'm really not sure.

If it was me, I'd go with 14" or 14.5" ones to be safe. That's basically what I have now, with my 16" shocks with about a 2" drop with the lowering brackets.

Thanks for the quick reply, and I'm only asking this because I'm a tad confused here so I hope you don't mind me asking... If I remember correctly, OAD's lowering brackets already was set for a 2" drop, and basically the new 16" shocks would have no affect in the lowering, am I correct?

And the reason why I asked about the 13.5" shocks was because I could find 16", 14.5", 13.5", 12.5" and 12" shocks, and 14" just weren't available. Anyway, I supposed if getting the 14.5" shocks which can yield a 1.5" drop, I shall be fine with that.

are the 13.5" shocks too short for a MP3 400 or the 14.5" ones better.

That's a really good question. When making the lowering brackets, OAD calculated that you didn't want to drop them more than 2". With a shorter stroke length than stock on these shocks, though, it might be OK. I'm really not sure.

If it was me, I'd go with 14" or 14.5" ones to be safe. That's basically what I have now, with my 16" shocks with about a 2" drop with the lowering brackets.

Thanks for the quick reply, and I'm only asking this because I'm a tad confused here so I hope you don't mind me asking... If I remember correctly, OAD's lowering brackets already was set for a 2" drop, and basically the new 16" shocks would have no affect in the lowering, am I correct?

And the reason why I asked about the 13.5" shocks was because I could find 16", 14.5", 13.5", 12.5" and 12" shocks, and 14" just weren't available. Anyway, I supposed if getting the 14.5" shocks which can yield a 1.5" drop, I shall be fine with that.

I think your final assessment is correct. Go for the 14.5" to get the 1.5" drop - which is plenty.

are the 13.5" shocks too short for a MP3 400 or the 14.5" ones better.

That's a really good question. When making the lowering brackets, OAD calculated that you didn't want to drop them more than 2". With a shorter stroke length than stock on these shocks, though, it might be OK. I'm really not sure.

If it was me, I'd go with 14" or 14.5" ones to be safe. That's basically what I have now, with my 16" shocks with about a 2" drop with the lowering brackets.

Thanks for the quick reply, and I'm only asking this because I'm a tad confused here so I hope you don't mind me asking... If I remember correctly, OAD's lowering brackets already was set for a 2" drop, and basically the new 16" shocks would have no affect in the lowering, am I correct?

And the reason why I asked about the 13.5" shocks was because I could find 16", 14.5", 13.5", 12.5" and 12" shocks, and 14" just weren't available. Anyway, I supposed if getting the 14.5" shocks which can yield a 1.5" drop, I shall be fine with that.

I think your final assessment is correct. Go for the 14.5" to get the 1.5" drop - which is plenty.

Have you installed them yet? I plan on ordering some myself this payday

They just arrived today. Probably won't have time until next week to install them. Besides, I still need to shop for some washers and use them as spacers like what CubsKing did.

By the way, just so you know, you can probably order the 14" ones and they can add about 10mm in length from the adjustment on the bottom if so desire. Only drawback with the 14", according to the seller's description of the item was that the max loads were 450lbs per pair, instead of the 650 that I ordered.

These shocks don't really have instructions included, so I will have to figure which way to turn to adjust the spring tension from the top. It says something about a 20mm length adjustment from there.

Last edited by felix168 on Fri Jun 27, 2014 8:42 am; edited 2 times in total

If you can find (or make) real spacers, that'd be better than having a stack of washers. (Or, as I did it, two stacks, one on each side of the eye.) It's really hard to get the widths right and then line it up and put a bolt through a stack of washers, an eye, and then another stack of washers...

If you can find (or make) real spacers, that'd be better than having a stack of washers. (Or, as I did it, two stacks, one on each side of the eye.) It's really hard to get the widths right and then line it up and put a bolt through a stack of washers, an eye, and then another stack of washers...

Basically it's going to be something like these, using 3 (approx 6mm altogether) of them glued together and place them on the inner side of the eyes, I think.

OAD took a look these on my bike at AmeriVespa. We're pretty sure that the springs on the 16" (400mm) springs are WAY over-sprung. The springs are rated for 650 pounds. When you push down on it, they barely move.

The shocks he has (or had) on his Cannonball bike were 340mm and used a thinner spring. I believe it's 7mm thick and supports about 450 pounds, but I don't know for sure. Hopefully, he'll take a caliper and measure them for us (hint, hint...)

And I will post a little update on my project... have been busy so I didn't even have time to finish it.

Went to Ace Hardware and got some rubber washers (12mm inside diameter) and stainless steel washers (30mm OD, 10mm) for the spacers.

Since there is a 10mm gap that needs to be filled, I have decided to use one stainless steel washer and one rubber washer on each side of the eyes. The rubber washers would all be trimmed to 30mm on the outside diameter (which I have already done but they didn't look like perfect circles ).

Last edited by felix168 on Fri Jun 27, 2014 8:39 am; edited 1 time in total

OAD took a look these on my bike at AmeriVespa. We're pretty sure that the springs on the 16" (400mm) springs are WAY over-sprung. The springs are rated for 650 pounds. When you push down on it, they barely move.

The shocks he has (or had) on his Cannonball bike were 340mm and used a thinner spring. I believe it's 7mm thick and supports about 450 pounds, but I don't know for sure. Hopefully, he'll take a caliper and measure them for us (hint, hint...)

Yep, it's severely over-sprung. I just did a few measurements and the results shocked me.

Now, before I give the numbers, I will warn you they're probably not exact. I was working by myself and using a measuring tape for sewing, so I don't think I got my numbers dead center of the eyes every time. But they're good enough to go by.

Up on the center stand, my shocks measure 405 mm.
Off the center stand, resting on the rear wheel, it measures 403 or 404 mm.

Yes, you read that right. The weight of the bike only causes it to sag 1-2 mm. With 68mm of travel, that's about 1.5% to 3% sag.

I put my helmet in the top box, laid a new 50 LB bag of salt sitting in my garage on top of the box, and draped my jacket over that. Then I laid across the passenger seat so I could reach down and measure the length. I'm about 200 LBs.

With that weight, as far back on the bike as I could get it, my shock length was about 395 mm. That works out to 14.7% sag.

In general, it's recommended that there should be about 30% sag in the shocks. I'm seeing less than half of that.

After I got my numbers, I noticed/remembered that I'd adjusted the adjustment ring of the shocks right after I'd first put them on while trying to find the sweet spot. It didn't seem to have made any difference, so I had left them alone. For the sake of completeness, I just went out, took them all the way to the top (took all the pre-load out) and did my measurements again. They were almost exactly the same, but about 3 mm longer. 408, 406, 398.

I don't have a comparison to the stock shocks. If someone still has stock shocks on and could do the same testing, I'd appreciate it. I've still got my stock shocks, so I may try it if I have time. But it'd be a lot easier for someone who didn't have to remount shocks, and it only takes a couple minutes...

Oh, something else of note. I busted out my digital caliper for the first time and took measurements of the thickness of the springs. The spring thickness on the 400 mm RFY shocks is between 8.4 and 8.5 mm. On the stock shocks, it's between 6.5 and 6.6 mm.

Yeah. Like I said, my numbers may not be exact, but they're in the right ballpark. And they definitely show those shocks aren't optimal, at least without some modifications.

I talked to LM15 on the phone today. He just got a set of the sames 16" ones as I did in yesterday. He's got a place nearby that does a lot of sales and work on racing bikes as well as shock rebuilds. He's going to take them over and see what they can do to make them better.

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